This relates to error control methods and apparatus especially useful in parallel processors such as those disclosed in the above-referenced U.S. Ser. Nos: 499,471 and 499,474 applications and U.S. Pat. No. 4,598,400.
As shown in FIG. 1A of U.S. Pat. No. 598,400 which is reproduced in FIG. 1, the computer system of those applications comprises a mainframe computer 10, a microcontroller 20, an array 30 of parallel processing integrated circuits 35, a data source 40, a first buffer and multiplexer/demultiplexer 50, first, second, third and fourth bidirectional bus control circuits 60, 65, 70, 75, a second buffer and multiplexer/demultiplexer 80, and a data sink 90. Mainframe computer 10 may be a suitably programmed commercially available general purpose computer such as a VAX.TM. computer manufactured by Digital Equipment Corp. Microcontroller 20 is an instruction sequencer of conventional design for generating a sequence of instructions that are applied to array 30 by means of a thirty-two bit parallel bus 22. Microcontroller 20 receives from array 30 a signal on line 26. This signal is a general purpose or GLOBAL signal that can be used for data output and status information. Bus 22 and line 26 are connected in parallel to each IC 35. As a result, signals from microcontroller 20 are applied simultaneously to each IC 35 in array 30 and the signal applied to microcontroller 20 on line 26 is formed by combining the signal outputs from all of ICs 35 of the array.
Array 30 contains thousands of identical ICs 35; and each IC 35 contains several identical processor/memories 36. In the embodiment disclosed in U.S. Pat. No. 4,598,400, it is indicated that the array may contain up to 32,768 (=2.sup.15) identical ICs 35; and each IC 35 may contain 32 (=2.sup.5) identical processor/memories 36. At the time of filing of this application for patent, arrays containing up to 4096 (=2.sup.12) identical ICs 35 containing 16 (=2.sup.4) identical processor/memories each have been manufactured and shipped by the assignee as Connection Machine.TM. computers.